Lock mounted with blind fasteners

ABSTRACT

A lock mounted with blind fasteners comprising a mounting plate fastened to a door or door jamb by screws passing through holes in the plate, a lock housing normally covering the mounting plate rendering the fastening screws inaccessable, the housing having a bore to detachably receive a lock core, movable bolt means on the housing operatively connected to the lock core, the bolt means preferably being a flat bar having a rock gear on one edge engaged to a spur gear mounted on the housing and driven by rotation of a first key in the lock core through a pair of connecting pins, the lock core being detachable from the bore in the housing in response to a second key, a second bore in the bottom of the bore in the housing adapted to receive a bolt extending therethrough and engagably in a threaded bore in the mounting plate thereby detachably securing the housing to the plate.

United States Patent Middleton et a1.

[54] LOCK MOUNTED WITH BLIND FASTENERS Y [72] Inventors: Richard E. Middleton, 517 Locust Ave., Hillside, NJ. 07205;,Donald Meyer, '26 Willow St., Glen Ridge,

[22] Filed: July 26, 1971 211 App]. No.: 166,223

[52] US. Cl. ..70/369, 70/232, 70/370, 70/DIG. 57 [51] Int. Cl. .;...E05b 9/08 [58] Field of Search ..70/232, 369, 370, 371, 427, 70/451, DIG. 57, 380, 379

[56] References Cited UNITED STATES PATENTS 1,512,939 10/1924 Ledin ..70/l34 1,561,771 11/1925 Best.... ...70/369 2,883,849 4/1959 Lorenzo.... ..70/427 3,564,879 2/1971 Bennett ..70/232 3,605,460 9/1971 Singer ..70/232 Primary Examiner-'Robert L. Wolfe Attorney-Popper, Bain, Bobis & Gilfillan [5 7] ABSTRACT A lock mounted with blind fasteners comprising a mounting plate fastened to a door or door jarnb by screws passing through holes in the plate, a lock housing normally covering the mounting plate rendering the fastening screws inaccessable, the housing having a bore to detachably receive a lock core, movable bolt means on the housing operatively connected to the lock core,the bolt means preferably being a flat bar having a rock gear on one edge engaged to a spur gear mounted on the housing and driven by rotation of a first key inthe lock core through a pair of connecting pins, the lock core being detachable from the bore in the'housing in response to a second key, a second bore in the bottom of the bore in the housing adapted to receive a bolt extending therethrough and enga g'ably in a threaded bore in the mounting plate thereby 'detachably securing the housing to the plate.

10 inaiyrit ief i PATENTED HEB 19 I972 SHEET 1 BF 3 FIG. 2

FIG.3

PMENTED 191972 3.706.212

sum 2 or 3 FIG. 4

PATENTEDUEC 19 1972 3,706,212

sum 3 OF 3 LOCK MOUNTED WITH BLIND FASTENERS BACKGROUND OF INVENTION The present invention relates to locks generally and specifically to a lock mounted with blind or inaccessable mounting fasteners. Such structures are useful for all locks but particularly useful for sequence locks.

The sequence lock is well known. and widely employed in large multiple-entrance buildings such as department stores, warehouses, discount or shopping center outlets and the like. A common sequence lock is provided with two lock cores, each operated by a different key. Both keys must be engaged to their respective cores in order to operate the lock. One key is removable from its lock core only when the lock is open and the other only when the lock is closed-One key of each lock is common to an adjacent lock in the sequence.

The locks are placed upon the entrances to the building beginning with a chosen prime entrance. The prime entrance lock is actuated by use of a pair of dissimilar keys. One key is removable when the lock is open, both keys are removable when the lock is closed, unlike the remaining locks of the sequence.

The key which is removable from the prime entrance lock when open is common to one of the two lock cores of the lock next in sequence. The other key of the pair for the second lock in the sequence is trapped or unremovable until that second lock is opened by use of the key common to the prime entrance lock. However, when the second lock in the sequence is opened, the key which was unremovable when it was locked become removable and is common to one of the two lock cores in the third lock of the sequence. The third and subsequent locks in the sequence are unlocked in an analogous manner. When the last lock in the sequence is opened, one of its two keys may be removed and retained against unauthorized locking of any of the locks. The reverse procedure is employed to lock the locks in reverse sequence.

The sequence lock compels the opening of all entrances if the last entrance of the sequence must be opened to use the building. Additionally, selected entrances cannot be overlooked which constitute a fire hazard.

Conversely, all locks must be locked if the last to be locked in the sequence is coupled with a burglar alarm system which must be actuated.

Sequence locks are usually placed on the interior side of entrances to minimize the danger of tampering by persons outside the building. However, existing sequence locks are fastened to the inside of a door or jamb by screws or the like which are exposed.

Experience has shown that a significantly large number of thefts from large multiple-entrance buildings has occurred by simple removal of the lock from the door or jamb by persons who have gained access to the building during hours when the public is admitted and have secreted themselves inside of the building at closing time.

Therefore, it is among the objects and advantages of the present invention to provide a lock in which the fasteners securing the lock to the door or jamb are inaccessable in normal operation.

Another object of the present invention is to provide a lock as aforesaid in which access to the fasteners securing the lock to the door or jamb is gained only after removal of a lock core from the lock housing by means of a select key dissimilar from the key employed to actuate the lock.

A further object of the invention is to provide a lock .as aforesaid employ well known removable lock cores frequently employed in sequence locks.

Yet another object of the invention is to provide a lock as aforesaid in which the removal of a lock as aforesaid in which the removal of a lock core provides access to means fastening the lock housing and bolt mechanism to a mounting plate secured to a door or jamb by fasteners covered by the lock housing when the housing is fastened to the mounting plate.

SUMMARY OF INVENTION A lock mourited with blind fasteners comprising a mounting plate, first fastening means on the mounting plate for securing it to a surface, a lock housing detachably secured to the mounting plate, the housing having a bore to receive a lock core, a lock core detachably seated within the bore, bolt means mounted on the housing and operatively connected to the lock core, the lock core being responsive to first key means to operate the bolt means, and responsiveto second key means for attachment and detachment to and from the bore, second fastening means for securing the housing to the mounting plate, the second fastening means being accessible from within the bore only when the lock core is detached from the bore by means of the second key means, the first said fastening means being inaccessible when the lock housing is secured to the mounting plate by the second said fastening means.

PREFERRED EMBODIMENT OF INVENTION The objects and advantages aforesaid as well as other objects and advantages maybe achieved by the lock mounted with blind fasteners claimed herein a preferred embodiment of which is illustrated in the drawings in which:

FIG. 1 is a side elevational cross-sectional view of the lock taken along line l-l of FIG. 2 looking in the direction of the arrows;

FIG. 2 is a front elevational view of the lock housing;

FIG. 3 is a rear elevational view of the lock housing with the mounting plate removed to one side and reversed to show the front of the mounting plate;

FIG. 4 is a front elevational view of a lock core;

FIG. 5 is a side elevational view of the lock core shown in FIG. 4;

FIG. 6 is a rear elevational view of the lock core shown in FIGS. 4 and 5 mounted in a bore in the lock housing;

FIG. 7 is a rear elevational view of the lock housing with the mounting plate bolt, and bolt drive mechanism removed;

FIG. 8 is a view in perspective of a bolt-drive spur gear and pin mechanism.

Referring now to the drawings in detail, a sequence lock is illustrated. However, the invention may be embodied in other than a sequence lock although the invention is particularly well adapted for incorporation in sequence locks.

The lock comprises a solid housing 11 which may be fabricated of aluminum or some other strong material resistant to forcing, cutting or the like. The front of the housing is provided with a pair of vertically spacedapart blind bores 13 and 14 extending rearwardly. The cross-sectional configuration of each of the bores 13 and 14 is that of vertically aligned overlapping cylinders in the front portion and an oval in the rear portion. The front portions define a pair of horizontally opposed inwardly extending ribs 15 and 16 defined by the intersection of the overlapping cylindrical portions. The rear end of the ribs 15 and 16 define abutments l7 and 18 respectively most clearly shown in FIG. 6 the functional value of which will be described later.

The rear of the housing 11 is provided with a recess 19 to accommodate a mounting plate 20. The top and bottom edges of the recess 19 are each provided with a horizontal channel respectively 21 and 22. The top and bottom edges of the mounting plate 20 are each provided with flanges respectively 23 and 24. Flange channels 21 and 22 slidably receive flanges 23 and 24, slidably mounting the plate 20 to the rear of the housing 11. The plate is dimensioned such that its rearmost surface is coplanar with the rearmost surface of the housing 11.

The rear of the housing 11 is provided with a deep, horizontal bolt channel 25 contiguous with recess 19, best shown in FIG. 7. The front face 26 of the bolt channel 25 is provided with a horizontal guide receiving limit groove 27.-

A pair of vertically aligned generally circular counterbores, respective 28 and 29, communicate with the bolt channel on the top and bottom edges thereof. Each of the counterbores 28 and 29 are provided with a pair of opposed horizontally extending relatively shallow recesses, respectively 30-30 and 31-31, each pair of which is provided with a tapped screw hole, 32-32 and 33-33. Each of the counterbores 28 and 29 is provided with bushing receiving bore, respectively 34 and 35, communicating with bores 13 and 14 respectively extending rearwardly from the front 12 of the housing 11.

A pair of bolt drive spur gear and pin mechanism 36 are mounted in the housing 11. The said mechanism, illustrated in perspective in FIG. 8 comprises a spur gear 37 having a bushing 38 formed on the front face thereof. A pair of elongated, relatively thin, cylindrical parallel pins 39-39 extend forwardly from the bushing 38.

One of each of the spur gear and pin mechanisms 36 is rotatably mounted in each of the counterbores 28 and 29, the bushing 38 seating within the bores 34 and 35. The pins 39-39 extend forwardly into the bores 13 and 14 communicating with the front 12 of the housing 11. A retainer plate 40 seated within each of the shallow recesses 30-30 and 31-31 and secured by screws 41 threadably engaged to the tapped screws holes 32- 32 and 33-33 retain the spur gear and pin mechanisms 36 in place.

A generally rectangular, flat-faced bolt or latch 42 is slidably mounted in the channel 25. The top and bottomedges of the bolt 42 are provided with rack gears respectively 43 and 44 which mesh with the spur gears 37 on the respective spur gear and pin mechanisms 36-36. The front face of the bolt 42 is provided with a pin 45 which is slidably engaged to the limit groove 27.

Bore 14 extending rearwardly from the front 12 of housing 11 is provided with a bolt receiving bore 46 communicating between the rear of bore 14 and the front of the recess 19 accommodating the mounting plate 20. The mounting plate 20 is provided with a tapped bolt hole 47 which is adapted to lie in registration with the bore 46 when the plate 20 is mounted to the housing 11 with side edges in registration.

The mounting plate 20 is also provided with four screw holes 48,48, etc. to receive fastening screws 49,49, etc. The front face 50 of the mounting plate 20 is countersunk at each of the holes 48 so that the screws 49 lie flush therewith.

A pair of lock cores 51 and 52 are detachably respectively in the bores 13 and 14. The lock cores 51 and 52 are of wellknown conventional design and need no further description of their internal construction. The cores 51 and Marc each provided with elongated holes 53 to receive the pins 39-39 on the spur gear and pin mechanisms. Rotation of the internal mechanism of the lock core rotates the pins 39-39 and hence the spur gears 37-37. Each of the lock cores 51 and 52 are operated by dissimilar keys to rotate the pins 39-39.

The cores 51 and 52 are detachably secured within the respective bores 13 and 14 by means of a laterally displaceably lug 54 mounted on the rearward portion of the core which is extendable upon limited rotation to engage abutment 17 defined by the rearward edge of rib 15 or 16. Rotation of lug 54 is accomplished by a special key insertably in the core and dissimilar to the keys employed to rotate the pins 39-39.

In operation, the mounting plate 20 is attached to a door or door jamb by means of fastening screws 49,49, etc. extending through holes 48, 48, etc. The housing 11 is engaged to the mounting plate 20 by sliding the flanges 23, 24 of the plate 20 into the grooves 21, 22 of the rear of the housing 11 until the respective side edges are in registration. in this position, the tapped bolt hole 47 of the plate 20 is in registration with the bore 46 communicating between the rear of the bore 14 and the recess 17. A bolt 55 is inserted through the bore 46 and threadably engaged to the hole 47 to secure the housing 11 to the plate 20. The lock core 52 is inserted into bore 14 and secured therein by means of displacing the lug 54 by a special key. The other lock core is similarly secured in bore 13.

When keys are inserted in both cores 51 and 52, both spur gears and pin mechanisms 36 are rotatable to move the bolt or latch 42 to either the locked or unlocked position. If one of the cores 51 or 52 is lacking a key, its cooperative spur gear and pin mechanism will not rotate preventing movement of the bolt or latch 42.

The housing 11 covers the holes 48,48, etc. and the cooperative fastening screws 49,49 securing the plate 20 to the door or door jamb, denying access thereto until the housing 11 is displaced.

The spur gear and pin mechanism 36 is also shown with a pair of intersecting wedge-shaped recess segments 56,56 in the face of the spur gear 37. This permits rotation of the key in the lock core approximately without effecting movement of the bolt or latch 42. Such free rotation of the key facilitates removal of the key from the core in the lock on the prime entrance without changing the status of the latch or bolt 42.

The foregoing description is merely intended to illustrate an embodiment of the invention. The component parts have been shown and described. They each may have substitutes which may perform a substantially similar function; such substitutes may be known as proper substitutes for the said components and may have actually been known or invented before the present invention.

What is claimed is:

l. A lock mounted with blind fasteners comprising,

a. a mounting plate;

b. first fastening means on the mounting plate for securing it to a surface;

c. a lock housing detachably secured to the mounting plate, the housing having a bore to receive a lock core;

. a lock core detachably seated within the bore;

e. bolt means mounted on the housing and operatively connected to the lock core;

the lock core being responsive to first key means to operate the bolt means, and responsive to second key means for attachment and detachment to and from the bore;

g. second fastening means for securing the housing to the mounting plate, the second fastening means being accessible from within the bore only when the lock core is detached from the bore by means of the second key means;

h. the first said fastening means being inaccessible when the lock housing is secured to the mounting plate by the second said fastening means.

2. A lock mounted with blind fasteners comprising,

a. the structure in accordance with claim 1 and b. cooperative means on the lock housing and mounting plate positively preventing relative rotational movement between them when the said second fastening means are engaged.

3. A lock mounted with blind fasteners comprising,

a. the structure in accordance with claim 2 in which b. said cooperative means are a slidably engaged groove and flange on the lock housing and mounting plate.

4. A lock mounted with blind fasteners comprising,

a. the structure in accordance with claim 1, in which b. the said second fastening means are a transverse passage in the housing extending rearwardly from the rear end of the said bore and communicating with the mounting plate; c. the mounting plate having a threaded bore registrable with the said transverse passage, and d. a bolt extending through the passage and threadably engaged in the threaded bore. 5. A lock mounted with blind fasteners comprising, a. the structure in accordance with claim 4 and b. cooperative means on the lock housing and mounting plate positively preventing relative rotational movement between them where the said second fastening means are engaged. 6. A lock mounted with blind fasteners comprising, a. the structure in accordance with claim 5 in which b. said cooperative means are a slidably engaged groove and flange on the lock housing and mounting plate. A lock mounted with blind fasteners comprising, the structure in accordance with claim 1 a rack ear on the bolt means' a spur gear mounted on the housing meshed with the spur gear, the spur gear rotating in response to rotation of the core by means of the first key means. A lock mounted with blind fasteners comprising, the structure in accordance with claim 7 and cooperative means on the lock housing and mounting plate positively preventing relative rotational movement between them when the said second fastening means are engaged. A look mounted with blind fasteners comprising, the structure in accordance with claim 8 in which said cooperative means are a slidably engaged groove and flange on the lock housing and mounting plate. 10. A lock mounted with blind fasteners comprising, a. the structure in accordance with claim 8 in which b. the said second fastening means are a transverse passage in the housing extending rearwardly from the rear end of the said bore and communicating with the mounting plate; 0. the mounting plate having a threaded bore registrable with the said transverse passage, and d. a bolt extending through the passage and threadably engaged in the threaded bore. 

1. A lock mounted with blind fasteners comprising, a. a mounting plate; b. first fastening means on the mounting plate for securing it to a surface; c. a lock housing detachably secured to the mounting plate, the housing having a bore to receive a lock core; d. a lock core detachably seated within the bore; e. bolt means mounted on the housing and operatively connected to the lock core; f. the lock core being responsive to first key means to operate the bolt means, and responsive to second key means for attachment and detachment to and from the bore; g. second fastening means for securing the housing to the mounting plate, the second fastening means being accessible from within the bore only when the lock core is detached from the bore by means of the second key means; h. the first said fastening means being inaccessible when the lock housing is secured to the mounting plate by the second said fastening means.
 2. A lock mounted with blind fasteners comprising, a. the structure in accordance with claim 1 and b. cooperative means on the lock housing and mounting plate positively preventing relative rotational movement between them when the said second fastening means are engaged.
 3. A lock mounted with blind fasteners comprising, a. the structure in accordance with claim 2 in which b. said cooperative means are a slidably engaged groove and flange on the lock housing and mounting plate.
 4. A lock mounted with blind fasteners comprising, a. the structure in accordance with claim 1, in which b. the said second fastening means are a transverse passage in the housing extending rearwardly from the rear end of the said bore and communicating with the mounting plate; c. the mounting plate having a threaded bore registrable with the said transverse passage, and d. a bolt extending through the passage and threadably engaged in the threaded bore.
 5. A lock mounted with blind fasteners comprising, a. the structure in accordance with claim 4 and b. cooperative means on the lock housing and mounting plate positively preventing relative rotational movement between them where the said second fastening means are engaged.
 6. A lock mounted with blind fasteners comprising, a. the structure in accordance with claim 5 in which b. said cooperative means are a slidably engaged groove and flange on the lock housing and mounting plate.
 7. A lock mounted with blind fasteners comprising, a. the structure in accordance with claim 1 b. a rack gear on the bolt means; c. a spur gear mounted on the housing meshed with the rack gear; d. transmission means connecting the lock core and the spur gear, the spur gear rotating in response to rotation of the core by means of the first key means.
 8. A lock mounted with blind fasteners comprising, a. the structure in accordance with claim 7 and b. cooperative means on the lock housing and mounting plate positively preventing relative rotational movement between them when the said second fastening means are engaged.
 9. A lock mounted with blind fasteners comprising, a. the structure in accordance with claim 8 in which b. said cooperative means are a slidably engaged groove and flange on the lock housing and mounting plate.
 10. A lock mounted with blind fasteners comprising, a. the structure in accordance with claim 8 in which b. the said second fastening means are a transverse passage in the housing extending rearwardly from the rear end of the said bore and communicating with the mounting plate; c. the mounting plate having a threaded bore registrable with the said transverse passage, and d. a bolt extending through the passage and threadably engaged in the threaded bore. 